首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   693篇
  免费   0篇
  国内免费   35篇
安全科学   55篇
废物处理   46篇
环保管理   54篇
综合类   62篇
基础理论   85篇
环境理论   1篇
污染及防治   297篇
评价与监测   89篇
社会与环境   35篇
灾害及防治   4篇
  2023年   22篇
  2022年   78篇
  2021年   72篇
  2020年   15篇
  2019年   25篇
  2018年   16篇
  2017年   31篇
  2016年   25篇
  2015年   13篇
  2014年   18篇
  2013年   67篇
  2012年   33篇
  2011年   42篇
  2010年   27篇
  2009年   25篇
  2008年   20篇
  2007年   28篇
  2006年   13篇
  2005年   12篇
  2004年   10篇
  2003年   15篇
  2002年   16篇
  2001年   15篇
  2000年   9篇
  1999年   8篇
  1998年   3篇
  1997年   7篇
  1996年   3篇
  1994年   2篇
  1993年   2篇
  1992年   2篇
  1991年   6篇
  1990年   3篇
  1988年   3篇
  1987年   4篇
  1986年   2篇
  1985年   4篇
  1984年   4篇
  1983年   3篇
  1982年   3篇
  1981年   2篇
  1980年   4篇
  1979年   4篇
  1978年   2篇
  1974年   1篇
  1971年   1篇
  1968年   1篇
  1962年   1篇
  1961年   1篇
  1959年   1篇
排序方式: 共有728条查询结果,搜索用时 15 毫秒
281.
Environment, Development and Sustainability - Environmental degradation has become an important issue for countries worldwide due to increase in carbon emission in recent years. It is an important...  相似文献   
282.
283.
284.
285.
ABSTRACT: A solution procedure to solve the inverse problem in ground water, based on lumped approach, has been proposed. The method has the following advantages: 1) exact determination of the boundary conditions and the physical laws of flow through porous media is not required; 2) all errors of approximation in describing the boundary conditions, physical laws, and the aquifer properties are lumped into the surrogate parameters; and 3) the same mathematical model can be employed both in the identification process and in the subsequent management studies. The optimal values of the surrogate parameters are found by using a multidimensional unconstrained optimization code devised by Powell. The solution procedure and the convergence characteristics of the proposed algorithm have been illustrated by two hypothetical problems.  相似文献   
286.
5-Bromoindole carboxylic acid and substituted indoles were administered parenterally to hamsters infected with an Egyptian strain of S. mansoni, to assess their antischistosomal activity. 5-Bromoindole showed a significant hepatic shift in 59 percent of treated hamsters. The results suggest that modification of the indole nucleus may produce a series of antischistosomal agents.  相似文献   
287.
288.
Activities in offshore oil and gas (OOG) that cause environmental impacts can be systematically managed through an environmental management system (EMS). Environmental performance evaluation (EPE) is an essential part of an EMS. However, previous studies on EPE indicate that existing lists of indicators little insight into how indicators are modified to more accurately assess environmental performance.In this paper, a way is proposed to identify and define specific environmental performance indicators on a case-by-case basis, which consists of five steps: (1) describing environmental requirements; (2) determining favourable outcomes corresponding to the requirements; (3) identifying required activities or issues to achieve the outcomes; (4) searching for proper measures of the activities or issues; and (5) generating a list of key indicators. Based on these steps, a quality function deployment (QFD) approach is developed to determine key indicators and evaluate environmental performance. To handle uncertainties in QFD, the decision makers’ evaluations are quantified through rough numbers using the concept of rough sets. The outputs of the proposed approach are different environmental performance indices. Using these indices, decision makers can easily determine whether an improved performance has been achieved through an EMS. The proposed approach is transparent and promising for use as a unified tool for EPE. An application of the proposed approach is demonstrated through a numerical example.  相似文献   
289.
Zn-air batteries (ZABs), especially the secondary batteries, have engrossed a great interest because of its high specific energy, economical and high safety. However, due to the insufficient activity and stability of bifunctional electrocatalysts for air-cathode oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) processes, the practical application of rechargeable ZABs is seriously hindered. In the effort of developing high active, stable and cost-effective electrocatalysts, transition metal nitrides (TMNs) have been regarded as the candidates due to their high conductivity, strong corrosion-resistance, and bifunctional catalytic performance. In this paper, the research progress in TMNs-based material as ORR and OER electrocatalysts for ZABs is discussed with respect to their synthesis, chemical/physical characterization, and performance validation/optimization. The surface/interface nanoengineering strategies such as defect engineering, support binding, heteroatom introduction, crystal plane orientation, interface construction and small size effect, the physical and chemical properties of TMNs-based electrocatalysts are emphasized with respect to their structures/morphologies, composition, electrical conductivity, specific surface area, chemical stability and corrosion resistance. The challenges of TMNs-based materials as bifunctional air-cathode electrocatalysts in practical application are evaluated, and numerous research guidelines to solve these problems are put forward for facilitating further research and development.  相似文献   
290.
Environmental Science and Pollution Research - Metal–organic frameworks (MOFs) are a polymer hybrid family of compounds comprising metal ions that have been deliberately incorporated in...  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号